Method for selecting bwp and device supporting the same

ABSTRACT

Provided are a method of selecting BWP and a device supporting the method. According to one embodiment of the present invention, the method includes: configuring multiple bandwidth parts (BWPs) for a cell; activating a first BWP among the multiple BWPs; acquiring information on congestion of at least one of the multiple BWPs; and switching to a second BWP among the multiple BWPs from the first BWPs, based on the acquired information on congestion.

TECHNICAL FIELD

The present invention relates to a wireless communication system, andmore particularly, to a method for selecting BWP and a device supportingthe same.

BACKGROUND

Efforts have been made to develop an improved 5^(th)-generation (5G)communication system or a pre-5G communication system in order tosatisfy a growing demand on radio data traffic after commercializationof a 4^(th)-generation (4G) communication system. A standardization actfor a 5G mobile communication standard work has been formally started in3GPP, and there is ongoing discussion in a standardization working groupunder a tentative name of a new radio access (NR).

Meanwhile, an upper layer protocol defines a protocol state toconsistently manage an operational state of a user equipment (UE), andindicates a function and procedure of the UE in detail. In thediscussion on the NR standardization, an RRC state is discussed suchthat an RRC_CONNECTED state and an RRC_IDLE state are basically defined,and an RRC_INACTIVE state is additionally introduced.

In NR, Supplementary Uplink (SUL) is introduced for enhancing ULcoverage. In case of SUL, the UE is configured with 2 ULs for one DL ofthe same cell, and uplink transmissions on those two ULs are controlledby the network to avoid overlapping PUSCH/PUCCH transmissions in time.Overlapping transmissions on PUSCH are avoided through scheduling whileoverlapping transmissions on PUCCH are avoided through configuration(PUCCH can only be configured for only one of the 2 ULs of the cell).

With Bandwidth Adaptation (BA), the receive and transmit bandwidth of aUE need not be as large as the bandwidth of the cell and can beadjusted: the width can be ordered to change (e.g. to shrink duringperiod of low activity to save power); the location can move in thefrequency domain (e.g. to increase scheduling flexibility); and thesubcarrier spacing can be ordered to change (e.g. to allow differentservices). A subset of the total cell bandwidth of a cell is referred toas a Bandwidth Part (BWP) and BA is achieved by configuring the UE withBWP(s) and telling the UE which of the configured BWPs is currently theactive one.

SUMMARY

According to a prior art, when congestion occurs on a particular BWP inunlicensed band, UE cannot move to non-congested BWP by itself withoutindication on PDCCH or expiry of BWP Inactivity Timer. Further, basestation may not quickly know whether congestion occurs in the BWP.

According to an embodiment of the present invention, a method performedby a user equipment (UE) in a wireless communication system is provided.The method may comprise: configuring multiple bandwidth parts (BWPs) fora cell; activating a first BWP among the multiple BWPs; acquiringinformation on congestion of at least one of the multiple BWPs; andswitching to a second BWP among the multiple BWPs from the first BWPs,based on the acquired information on congestion.

The multiple BWPs may be configured on unlicensed band.

The information on congestion of the at least one of the multiple BWPsmay include information on congestion of the first BWP.

The information on congestion of the at least one of the multiple BWPsmay include information on congestion of the second BWP.

The switching to the second BWP may be performed, when congestion levelof the first BWP is above a threshold informed by the cell.

The switching to the second BWP may be performed, when congestion levelof the second BWP is below a threshold informed by the cell.

The information on congestion may be acquired by carrier sensing.

The information on congestion may inform whether the at least one of themultiple BWPs is busy or free.

The switching to the second BWP may include considering the second BWPas an initial BWP or a default BWP.

The method may further comprise performing UL transmission on the secondBWP via random access procedure.

The UE may communicate with at least one of a mobile terminal, a networkor autonomous vehicles other than the UE.

According to another embodiment of the present invention, a userequipment (UE) in a wireless communication system is provided. The UEmay comprise: a memory; a transceiver; and a processor, operably coupledto the memory and the transceiver, and configured to: configure multiplebandwidth parts (BWPs) for a cell; activate a first BWP among themultiple BWPs; acquire information on congestion of at least one of themultiple BWPs; and switch to a second BWP among the multiple BWPs fromthe first BWPs, based on the acquired information on congestion.

The multiple BWPs may be configured on unlicensed band.

The information on congestion of the at least one of the multiple BWPsmay include information on congestion of the first BWP.

According to another embodiment of the present invention, a processorfor a wireless communication device in a wireless communication systemis provided. The processor may be configured to control the wirelesscommunication device to: configure multiple bandwidth parts (BWPs) for acell; activate a first BWP among the multiple BWPs; acquire informationon congestion of at least one of the multiple BWPs; and switch to asecond BWP among the multiple BWPs from the first BWPs, based on theacquired information on congestion.

According to embodiments of the present invention, the UE may provideuser service on BWP efficiently by moving to non-congested BWP byitself.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows examples of 5G usage scenarios to which the technicalfeatures of the present invention can be applied.

FIG. 2 shows an example of a wireless communication system to which thetechnical features of the present invention can be applied.

FIG. 3 shows an example of a wireless communication system to which thetechnical features of the present invention can be applied.

FIG. 4 shows another example of a wireless communication system to whichthe technical features of the present invention can be applied.

FIG. 5 shows a block diagram of a user plane protocol stack to which thetechnical features of the present invention can be applied.

FIG. 6 shows a block diagram of a control plane protocol stack to whichthe technical features of the present invention can be applied.

FIG. 7 shows scenarios for SUL.

FIG. 8 shows a scenario where 3 different BWPs are configured.

FIG. 9 shows a method for selecting BWP according to an embodiment ofthe present invention.

FIG. 10 shows a method for selecting BWP according to an embodiment ofthe present invention.

FIG. 11 shows more detailed UE to implement an embodiment of the presentinvention.

FIG. 12 shows an example of an AI device to which the technical featuresof the present invention can be applied.

FIG. 13 shows an example of an AI system to which the technical featuresof the present invention can be applied.

DETAILED DESCRIPTION

The technical features described below may be used by a communicationstandard by the 3rd generation partnership project (3GPP)standardization organization, a communication standard by the instituteof electrical and electronics engineers (IEEE), etc. For example, thecommunication standards by the 3GPP standardization organization includelong-term evolution (LTE) and/or evolution of LTE systems. The evolutionof LTE systems includes LTE-advanced (LTE-A), LTE-A Pro, and/or 5G newradio (NR). The communication standard by the IEEE standardizationorganization includes a wireless local area network (WLAN) system suchas IEEE 802.11a/b/g/n/ac/ax. The above system uses various multipleaccess technologies such as orthogonal frequency division multipleaccess (OFDMA) and/or single carrier frequency division multiple access(SC-FDMA) for downlink (DL) and/or uplink (UL). For example, only OFDMAmay be used for DL and only SC-FDMA may be used for UL. Alternatively,OFDMA and SC-FDMA may be used for DL and/or UL.

In this document, the term “/” and “,” should be interpreted to indicate“and/or.” For instance, the expression “A/B” may mean “A and/or B.”Further, “A, B” may mean “A and/or B.” Further, “A/B/C” may mean “atleast one of A, B, and/or C.” Also, “A, B, C” may mean “at least one ofA, B, and/or C.”

Further, in the document, the term “or” should be interpreted toindicate “and/or.” For instance, the expression “A or B” may comprise 1)only A, 2) only B, and/or 3) both A and B. In other words, the term “or”in this document should be interpreted to indicate “additionally oralternatively.”

FIG. 1 shows examples of 5G usage scenarios to which the technicalfeatures of the present invention can be applied.

The 5G usage scenarios shown in FIG. 1 are only exemplary, and thetechnical features of the present invention can be applied to other 5Gusage scenarios which are not shown in FIG. 1.

Referring to FIG. 1, the three main requirements areas of 5G include (1)enhanced mobile broadband (eMBB) domain, (2) massive machine typecommunication (mMTC) area, and (3) ultra-reliable and low latencycommunications (URLLC) area. Some use cases may require multiple areasfor optimization and, other use cases may only focus on only one keyperformance indicator (KPI). 5G is to support these various use cases ina flexible and reliable way.

eMBB focuses on across-the-board enhancements to the data rate, latency,user density, capacity and coverage of mobile broadband access. The eMBBaims ˜10 Gbps of throughput. eMBB far surpasses basic mobile Internetaccess and covers rich interactive work and media and entertainmentapplications in cloud and/or augmented reality. Data is one of the keydrivers of 5G and may not be able to see dedicated voice services forthe first time in the 5G era. In 5G, the voice is expected to beprocessed as an application simply using the data connection provided bythe communication system. The main reason for the increased volume oftraffic is an increase in the size of the content and an increase in thenumber of applications requiring high data rates. Streaming services(audio and video), interactive video and mobile Internet connectivitywill become more common as more devices connect to the Internet. Many ofthese applications require always-on connectivity to push real-timeinformation and notifications to the user. Cloud storage andapplications are growing rapidly in mobile communication platforms,which can be applied to both work and entertainment. Cloud storage is aspecial use case that drives growth of uplink data rate. 5G is also usedfor remote tasks on the cloud and requires much lower end-to-end delayto maintain a good user experience when the tactile interface is used.In entertainment, for example, cloud games and video streaming areanother key factor that increases the demand for mobile broadbandcapabilities. Entertainment is essential in smartphones and tabletsanywhere, including high mobility environments such as trains, cars andairplanes. Another use case is augmented reality and informationretrieval for entertainment. Here, augmented reality requires very lowlatency and instantaneous data amount.

mMTC is designed to enable communication between devices that arelow-cost, massive in number and battery-driven, intended to supportapplications such as smart metering, logistics, and field and bodysensors. mMTC aims ˜10 years on battery and/or ˜1 million devices/km2.mMTC allows seamless integration of embedded sensors in all areas and isone of the most widely used 5G applications. Potentially by 2020,internet-of-things (IoT) devices are expected to reach 20.4 billion.Industrial IoT is one of the areas where 5G plays a key role in enablingsmart cities, asset tracking, smart utilities, agriculture and securityinfrastructures.

URLLC will make it possible for devices and machines to communicate withultra-reliability, very low latency and high availability, making itideal for vehicular communication, industrial control, factoryautomation, remote surgery, smart grids and public safety applications.URLLC aims ˜1 ms of latency. URLLC includes new services that willchange the industry through links with ultra-reliability/low latency,such as remote control of key infrastructure and self-driving vehicles.The level of reliability and latency is essential for smart gridcontrol, industrial automation, robotics, drones control andcoordination.

Next, a plurality of use cases included in the triangle of FIG. 1 willbe described in more detail.

5G can complement fiber-to-the-home (FTTH) and cable-based broadband (orDOCSIS) as a means of delivering streams rated from hundreds of megabitsper second to gigabits per second. This high speed can be required todeliver TVs with resolutions of 4K or more (6K, 8K and above) as well asvirtual reality (VR) and augmented reality (AR). VR and AR applicationsinclude mostly immersive sporting events. Certain applications mayrequire special network settings. For example, in the case of a VR game,a game company may need to integrate a core server with an edge networkserver of a network operator to minimize delay.

Automotive is expected to become an important new driver for 5G, withmany use cases for mobile communications to vehicles. For example,entertainment for passengers demands high capacity and high mobilebroadband at the same time. This is because future users will continueto expect high-quality connections regardless of their location andspeed. Another use case in the automotive sector is an augmented realitydashboard. The driver can identify an object in the dark on top of whatis being viewed through the front window through the augmented realitydashboard. The augmented reality dashboard displays information thatwill inform the driver about the object's distance and movement. In thefuture, the wireless module enables communication between vehicles,information exchange between the vehicle and the supportinginfrastructure, and information exchange between the vehicle and otherconnected devices (e.g. devices accompanied by a pedestrian). The safetysystem allows the driver to guide the alternative course of action sothat he can drive more safely, thereby reducing the risk of accidents.The next step will be a remotely controlled vehicle or self-drivingvehicle. This requires a very reliable and very fast communicationbetween different self-driving vehicles and between vehicles andinfrastructure. In the future, a self-driving vehicle will perform alldriving activities, and the driver will focus only on traffic that thevehicle itself cannot identify. The technical requirements ofself-driving vehicles require ultra-low latency and high-speedreliability to increase traffic safety to a level not achievable byhumans.

Smart cities and smart homes, which are referred to as smart societies,will be embedded in high density wireless sensor networks. Thedistributed network of intelligent sensors will identify conditions forcost and energy-efficient maintenance of a city or house. A similarsetting can be performed for each home. Temperature sensors, windows andheating controllers, burglar alarms and appliances are all wirelesslyconnected. Many of these sensors typically require low data rate, lowpower and low cost. However, for example, real-time high-definition (HD)video may be required for certain types of devices for monitoring.

The consumption and distribution of energy, including heat or gas, ishighly dispersed, requiring automated control of distributed sensornetworks. The smart grid interconnects these sensors using digitalinformation and communication technologies to collect and act oninformation. This information can include supplier and consumerbehavior, allowing the smart grid to improve the distribution of fuel,such as electricity, in terms of efficiency, reliability, economy,production sustainability, and automated methods. The smart grid can beviewed as another sensor network with low latency.

The health sector has many applications that can benefit from mobilecommunications. Communication systems can support telemedicine toprovide clinical care in remote locations. This can help to reducebarriers to distance and improve access to health services that are notcontinuously available in distant rural areas. It is also used to savelives in critical care and emergency situations. Mobile communicationbased wireless sensor networks can provide remote monitoring and sensorsfor parameters such as heart rate and blood pressure.

Wireless and mobile communications are becoming increasingly importantin industrial applications. Wiring costs are high for installation andmaintenance. Thus, the possibility of replacing a cable with a wirelesslink that can be reconfigured is an attractive opportunity in manyindustries. However, achieving this requires that wireless connectionsoperate with similar delay, reliability, and capacity as cables and thattheir management is simplified. Low latency and very low errorprobabilities are new requirements that need to be connected to 5G.

Logistics and freight tracking are important use cases of mobilecommunications that enable tracking of inventory and packages anywhereusing location based information systems. Use cases of logistics andfreight tracking typically require low data rates, but require a largerange and reliable location information.

FIG. 2 shows an example of a wireless communication system to which thetechnical features of the present invention can be applied.

Referring to FIG. 2, the wireless communication system may include afirst device 210 and a second device 220.

The first device 210 includes a base station, a network node, atransmitting UE, a receiving UE, a wireless device, a wirelesscommunication device, a vehicle, a vehicle equipped with an autonomousdriving function, a connected car, a drone, an unmanned aerial vehicle(UAV), an artificial intelligence (AI) module, a robot, an AR device, aVR device, a mixed reality (MR) device, a hologram device, a publicsafety device, an MTC device, an IoT device, a medical device, afin-tech device (or, a financial device), a security device, aclimate/environmental device, a device related to 5G services, or adevice related to the fourth industrial revolution.

The second device 220 includes a base station, a network node, atransmitting UE, a receiving UE, a wireless device, a wirelesscommunication device, a vehicle, a vehicle equipped with an autonomousdriving function, a connected car, a drone, a UAV, an AI module, arobot, an AR device, a VR device, an MR device, a hologram device, apublic safety device, an MTC device, an IoT device, a medical device, afin-tech device (or, a financial device), a security device, aclimate/environmental device, a device related to 5G services, or adevice related to the fourth industrial revolution.

For example, the UE may include a mobile phone, a smart phone, a laptopcomputer, a digital broadcasting terminal, a personal digital assistant(PDA), a portable multimedia player (PMP), a navigation device, a slatepersonal computer (PC), a tablet PC, an ultrabook, a wearable device(e.g. a smartwatch, a smart glass, a head mounted display (HMD)). Forexample, the HMD may be a display device worn on the head. For example,the HMD may be used to implement AR, VR and/or MR.

For example, the drone may be a flying object that is flying by a radiocontrol signal without a person boarding it. For example, the VR devicemay include a device that implements an object or background in thevirtual world. For example, the AR device may include a device thatimplements connection of an object and/or a background of a virtualworld to an object and/or a background of the real world. For example,the MR device may include a device that implements fusion of an objectand/or a background of a virtual world to an object and/or a backgroundof the real world. For example, the hologram device may include a devicethat implements a 360-degree stereoscopic image by recording and playingstereoscopic information by utilizing a phenomenon of interference oflight generated by the two laser lights meeting with each other, calledholography. For example, the public safety device may include a videorelay device or a video device that can be worn by the user's body. Forexample, the MTC device and the IoT device may be a device that do notrequire direct human intervention or manipulation. For example, the MTCdevice and the IoT device may include a smart meter, a vending machine,a thermometer, a smart bulb, a door lock and/or various sensors. Forexample, the medical device may be a device used for the purpose ofdiagnosing, treating, alleviating, handling, or preventing a disease.For example, the medical device may be a device used for the purpose ofdiagnosing, treating, alleviating, or correcting an injury or disorder.For example, the medical device may be a device used for the purpose ofinspecting, replacing or modifying a structure or function. For example,the medical device may be a device used for the purpose of controllingpregnancy. For example, the medical device may include a treatmentdevice, a surgical device, an (in vitro) diagnostic device, a hearingaid and/or a procedural device, etc. For example, a security device maybe a device installed to prevent the risk that may occur and to maintainsafety. For example, the security device may include a camera, aclosed-circuit TV (CCTV), a recorder, or a black box. For example, thefin-tech device may be a device capable of providing financial servicessuch as mobile payment. For example, the fin-tech device may include apayment device or a point of sales (POS). For example, theclimate/environmental device may include a device for monitoring orpredicting the climate/environment.

The first device 210 may include at least one or more processors, suchas a processor 211, at least one memory, such as a memory 212, and atleast one transceiver, such as a transceiver 213. The processor 211 mayperform the functions, procedures, and/or methods of the presentinvention described below. The processor 211 may perform one or moreprotocols. For example, the processor 211 may perform one or more layersof the air interface protocol. The memory 212 is connected to theprocessor 211 and may store various types of information and/orinstructions. The transceiver 213 is connected to the processor 211 andmay be controlled to transmit and receive wireless signals.

The second device 220 may include at least one or more processors, suchas a processor 221, at least one memory, such as a memory 222, and atleast one transceiver, such as a transceiver 223. The processor 221 mayperform the functions, procedures, and/or methods of the presentinvention described below. The processor 221 may perform one or moreprotocols. For example, the processor 221 may perform one or more layersof the air interface protocol. The memory 222 is connected to theprocessor 221 and may store various types of information and/orinstructions. The transceiver 223 is connected to the processor 221 andmay be controlled to transmit and receive wireless signals.

The memory 212, 222 may be connected internally or externally to theprocessor 211, 212, or may be connected to other processors via avariety of technologies such as wired or wireless connections.

The first device 210 and/or the second device 220 may have more than oneantenna. For example, antenna 214 and/or antenna 224 may be configuredto transmit and receive wireless signals.

FIG. 3 shows an example of a wireless communication system to which thetechnical features of the present invention can be applied.

Specifically, FIG. 3 shows a system architecture based on anevolved-UMTS terrestrial radio access network (E-UTRAN). Theaforementioned LTE is a part of an evolved-UMTS (e-UMTS) using theE-UTRAN.

Referring to FIG. 3, the wireless communication system includes one ormore user equipment (UE) 310, an E-UTRAN and an evolved packet core(EPC). The UE 310 refers to a communication equipment carried by a user.The UE 310 may be fixed or mobile. The UE 310 may be referred to asanother terminology, such as a mobile station (MS), a user terminal(UT), a subscriber station (SS), a wireless device, etc.

The E-UTRAN consists of one or more evolved NodeB (eNB) 320. The eNB 320provides the E-UTRA user plane and control plane protocol terminationstowards the UE 10. The eNB 320 is generally a fixed station thatcommunicates with the UE 310. The eNB 320 hosts the functions, such asinter-cell radio resource management (RRM), radio bearer (RB) control,connection mobility control, radio admission control, measurementconfiguration/provision, dynamic resource allocation (scheduler), etc.The eNB 320 may be referred to as another terminology, such as a basestation (BS), a base transceiver system (BTS), an access point (AP),etc.

A downlink (DL) denotes communication from the eNB 320 to the UE 310. Anuplink (UL) denotes communication from the UE 310 to the eNB 320. Asidelink (SL) denotes communication between the UEs 310. In the DL, atransmitter may be a part of the eNB 320, and a receiver may be a partof the UE 310. In the UL, the transmitter may be a part of the UE 310,and the receiver may be a part of the eNB 320. In the SL, thetransmitter and receiver may be a part of the UE 310.

The EPC includes a mobility management entity (MME), a serving gateway(S-GW) and a packet data network (PDN) gateway (P-GW). The MME hosts thefunctions, such as non-access stratum (NAS) security, idle statemobility handling, evolved packet system (EPS) bearer control, etc. TheS-GW hosts the functions, such as mobility anchoring, etc. The S-GW is agateway having an E-UTRAN as an endpoint. For convenience, MME/S-GW 330will be referred to herein simply as a “gateway,” but it is understoodthat this entity includes both the MME and S-GW. The P-GW hosts thefunctions, such as UE Internet protocol (IP) address allocation, packetfiltering, etc. The P-GW is a gateway having a PDN as an endpoint. TheP-GW is connected to an external network.

The UE 310 is connected to the eNB 320 by means of the Uu interface. TheUEs 310 are interconnected with each other by means of the PC5interface. The eNBs 320 are interconnected with each other by means ofthe X2 interface. The eNBs 320 are also connected by means of the S1interface to the EPC, more specifically to the MME by means of theS1-MME interface and to the S-GW by means of the S1-U interface. The S1interface supports a many-to-many relation between MMEs/S-GWs and eNBs.

FIG. 4 shows another example of a wireless communication system to whichthe technical features of the present invention can be applied.

Specifically, FIG. 4 shows a system architecture based on a 5G NR. Theentity used in the 5G NR (hereinafter, simply referred to as “NR”) mayabsorb some or all of the functions of the entities introduced in FIG. 3(e.g. eNB, MME, S-GW). The entity used in the NR may be identified bythe name “NG” for distinction from the LTE/LTE-A.

Referring to FIG. 4, the wireless communication system includes one ormore UE 410, a next-generation RAN (NG-RAN) and a 5th generation corenetwork (5GC). The NG-RAN consists of at least one NG-RAN node. TheNG-RAN node is an entity corresponding to the eNB 320 shown in FIG. 3.The NG-RAN node consists of at least one gNB 421 and/or at least oneng-eNB 422. The gNB 421 provides NR user plane and control planeprotocol terminations towards the UE 410. The ng-eNB 422 provides E-UTRAuser plane and control plane protocol terminations towards the UE 410.

The 5GC includes an access and mobility management function (AMF), auser plane function (UPF) and a session management function (SMF). TheAMF hosts the functions, such as NAS security, idle state mobilityhandling, etc. The AMF is an entity including the functions of theconventional MME. The UPF hosts the functions, such as mobilityanchoring, protocol data unit (PDU) handling. The UPF an entityincluding the functions of the conventional S-GW. The SMF hosts thefunctions, such as UE IP address allocation, PDU session control.

The gNBs 421 and ng-eNBs 422 are interconnected with each other by meansof the Xn interface. The gNBs 421 and ng-eNBs 422 are also connected bymeans of the NG interfaces to the 5GC, more specifically to the AMF bymeans of the NG-C interface and to the UPF by means of the NG-Uinterface.

A protocol structure between network entities described above isdescribed. On the system of FIG. 3 and/or FIG. 4, layers of a radiointerface protocol between the UE and the network (e.g. NG-RAN and/orE-UTRAN) may be classified into a first layer (L1), a second layer (L2),and a third layer (L3) based on the lower three layers of the opensystem interconnection (OSI) model that is well-known in thecommunication system.

FIG. 5 shows a block diagram of a user plane protocol stack to which thetechnical features of the present invention can be applied. FIG. 6 showsa block diagram of a control plane protocol stack to which the technicalfeatures of the present invention can be applied.

The user/control plane protocol stacks shown in FIG. 5 and FIG. 6 areused in NR. However, user/control plane protocol stacks shown in FIG. 5and FIG. 6 may be used in LTE/LTE-A without loss of generality, byreplacing gNB/AMF with eNB/MME.

Referring to FIG. 5 and FIG. 6, a physical (PHY) layer belonging to L1.The PHY layer offers information transfer services to media accesscontrol (MAC) sublayer and higher layers. The PHY layer offers to theMAC sublayer transport channels. Data between the MAC sublayer and thePHY layer is transferred via the transport channels. Between differentPHY layers, i.e., between a PHY layer of a transmission side and a PHYlayer of a reception side, data is transferred via the physicalchannels.

The MAC sublayer belongs to L2. The main services and functions of theMAC sublayer include mapping between logical channels and transportchannels, multiplexing/de-multiplexing of MAC service data units (SDUs)belonging to one or different logical channels into/from transportblocks (TB) delivered to/from the physical layer on transport channels,scheduling information reporting, error correction through hybridautomatic repeat request (HARQ), priority handling between UEs by meansof dynamic scheduling, priority handling between logical channels of oneUE by means of logical channel prioritization (LCP), etc. The MACsublayer offers to the radio link control (RLC) sublayer logicalchannels.

The RLC sublayer belong to L2. The RLC sublayer supports threetransmission modes, i.e. transparent mode (TM), unacknowledged mode(UM), and acknowledged mode (AM), in order to guarantee various qualityof services (QoS) required by radio bearers. The main services andfunctions of the RLC sublayer depend on the transmission mode. Forexample, the RLC sublayer provides transfer of upper layer PDUs for allthree modes, but provides error correction through ARQ for AM only. InLTE/LTE-A, the RLC sublayer provides concatenation, segmentation andreassembly of RLC SDUs (only for UM and AM data transfer) andre-segmentation of RLC data PDUs (only for AM data transfer). In NR, theRLC sublayer provides segmentation (only for AM and UM) andre-segmentation (only for AM) of RLC SDUs and reassembly of SDU (onlyfor AM and UM). That is, the NR does not support concatenation of RLCSDUs. The RLC sublayer offers to the packet data convergence protocol(PDCP) sublayer RLC channels.

The PDCP sublayer belong to L2. The main services and functions of thePDCP sublayer for the user plane include header compression anddecompression, transfer of user data, duplicate detection, PDCP PDUrouting, retransmission of PDCP SDUs, ciphering and deciphering, etc.The main services and functions of the PDCP sublayer for the controlplane include ciphering and integrity protection, transfer of controlplane data, etc.

The service data adaptation protocol (SDAP) sublayer belong to L2. TheSDAP sublayer is only defined in the user plane. The SDAP sublayer isonly defined for NR. The main services and functions of SDAP include,mapping between a QoS flow and a data radio bearer (DRB), and markingQoS flow ID (QFI) in both DL and UL packets. The SDAP sublayer offers to5GC QoS flows.

A radio resource control (RRC) layer belongs to L3. The RRC layer isonly defined in the control plane. The RRC layer controls radioresources between the UE and the network. To this end, the RRC layerexchanges RRC messages between the UE and the BS. The main services andfunctions of the RRC layer include broadcast of system informationrelated to AS and NAS, paging, establishment, maintenance and release ofan RRC connection between the UE and the network, security functionsincluding key management, establishment, configuration, maintenance andrelease of radio bearers, mobility functions, QoS management functions,UE measurement reporting and control of the reporting, NAS messagetransfer to/from NAS from/to UE.

In other words, the RRC layer controls logical channels, transportchannels, and physical channels in relation to the configuration,reconfiguration, and release of radio bearers. A radio bearer refers toa logical path provided by L1 (PHY layer) and L2 (MAC/RLC/PDCP/SDAPsublayer) for data transmission between a UE and a network. Setting theradio bearer means defining the characteristics of the radio protocollayer and the channel for providing a specific service, and setting eachspecific parameter and operation method. Radio bearer may be dividedinto signaling RB (SRB) and data RB (DRB). The SRB is used as a path fortransmitting RRC messages in the control plane, and the DRB is used as apath for transmitting user data in the user plane.

An RRC state indicates whether an RRC layer of the UE is logicallyconnected to an RRC layer of the E-UTRAN. In LTE/LTE-A, when the RRCconnection is established between the RRC layer of the UE and the RRClayer of the E-UTRAN, the UE is in the RRC connected state(RRC_CONNECTED). Otherwise, the UE is in the RRC idle state (RRC_IDLE).In NR, the RRC inactive state (RRC_INACTIVE) is additionally introduced.RRC_INACTIVE may be used for various purposes. For example, the massivemachine type communications (MMTC) UEs can be efficiently managed inRRC_INACTIVE. When a specific condition is satisfied, transition is madefrom one of the above three states to the other.

A predetermined operation may be performed according to the RRC state.In RRC_IDLE, public land mobile network (PLMN) selection, broadcast ofsystem information (SI), cell re-selection mobility, core network (CN)paging and discontinuous reception (DRX) configured by NAS may beperformed. The UE shall have been allocated an identifier (ID) whichuniquely identifies the UE in a tracking area. No RRC context stored inthe BS.

In RRC_CONNECTED, the UE has an RRC connection with the network (i.e.E-UTRAN/NG-RAN). Network-CN connection (both C/U-planes) is alsoestablished for UE. The UE AS context is stored in the network and theUE. The RAN knows the cell which the UE belongs to. The network cantransmit and/or receive data to/from UE. Network controlled mobilityincluding measurement is also performed.

Most of operations performed in RRC_IDLE may be performed inRRC_INACTIVE. But, instead of CN paging in RRC_IDLE, RAN paging isperformed in RRC_INACTIVE. In other words, in RRC_IDLE, paging formobile terminated (MT) data is initiated by core network and paging areais managed by core network. In RRC_INACTIVE, paging is initiated byNG-RAN, and RAN-based notification area (RNA) is managed by NG-RAN.Further, instead of DRX for CN paging configured by NAS in RRC_IDLE, DRXfor RAN paging is configured by NG-RAN in RRC_INACTIVE. Meanwhile, inRRC_INACTIVE, 5GC-NG-RAN connection (both C/U-planes) is established forUE, and the UE AS context is stored in NG-RAN and the UE. NG-RAN knowsthe RNA which the UE belongs to.

NAS layer is located at the top of the RRC layer. The NAS controlprotocol performs the functions, such as authentication, mobilitymanagement, security control.

The physical channels may be modulated according to OFDM processing andutilizes time and frequency as radio resources. The physical channelsconsist of a plurality of orthogonal frequency division multiplexing(OFDM) symbols in time domain and a plurality of subcarriers infrequency domain. One subframe consists of a plurality of OFDM symbolsin the time domain. A resource block is a resource allocation unit, andconsists of a plurality of OFDM symbols and a plurality of subcarriers.In addition, each subframe may use specific subcarriers of specific OFDMsymbols (e.g. first OFDM symbol) of the corresponding subframe for aphysical downlink control channel (PDCCH), i.e. L1/L2 control channel. Atransmission time interval (TTI) is a basic unit of time used by ascheduler for resource allocation. The TTI may be defined in units ofone or a plurality of slots, or may be defined in units of mini-slots.

The transport channels are classified according to how and with whatcharacteristics data are transferred over the radio interface. DLtransport channels include a broadcast channel (BCH) used fortransmitting system information, a downlink shared channel (DL-SCH) usedfor transmitting user traffic or control signals, and a paging channel(PCH) used for paging a UE. UL transport channels include an uplinkshared channel (UL-SCH) for transmitting user traffic or control signalsand a random access channel (RACH) normally used for initial access to acell.

Different kinds of data transfer services are offered by MAC sublayer.Each logical channel type is defined by what type of information istransferred. Logical channels are classified into two groups: controlchannels and traffic channels.

Control channels are used for the transfer of control plane informationonly. The control channels include a broadcast control channel (BCCH), apaging control channel (PCCH), a common control channel (CCCH) and adedicated control channel (DCCH). The BCCH is a DL channel forbroadcasting system control information. The PCCH is DL channel thattransfers paging information, system information change notifications.The CCCH is a channel for transmitting control information between UEsand network. This channel is used for UEs having no RRC connection withthe network. The DCCH is a point-to-point bi-directional channel thattransmits dedicated control information between a UE and the network.This channel is used by UEs having an RRC connection.

Traffic channels are used for the transfer of user plane informationonly. The traffic channels include a dedicated traffic channel (DTCH).The DTCH is a point-to-point channel, dedicated to one UE, for thetransfer of user information. The DTCH can exist in both UL and DL.

Regarding mapping between the logical channels and transport channels,in DL, BCCH can be mapped to BCH, BCCH can be mapped to DL-SCH, PCCH canbe mapped to PCH, CCCH can be mapped to DL-SCH, DCCH can be mapped toDL-SCH, and DTCH can be mapped to DL-SCH. In UL, CCCH can be mapped toUL-SCH, DCCH can be mapped to UL-SCH, and DTCH can be mapped to UL-SCH.

In NR, Supplementary Uplink (SUL) is introduced for enhancing ULcoverage. In case of SUL, the UE is configured with 2 ULs for one DL ofthe same cell, and uplink transmissions on those two ULs are controlledby the network to avoid overlapping PUSCH/PUCCH transmissions in time.Overlapping transmissions on PUSCH are avoided through scheduling whileoverlapping transmissions on PUCCH are avoided through configuration(PUCCH can only be configured for only one of the 2 ULs of the cell). Inaddition, initial access is supported in each of the uplink. For initialaccess in a NR cell configured with SUL, the UE may select the SULcarrier if and only if the measured quality of the DL is lower than abroadcast threshold. Once started, all uplink transmissions of therandom access procedure remain on the selected carrier.

FIG. 7 shows scenarios for SUL. Referring to FIG. 7, Up to 2 UL carriersare configurable per each DL carrier in a cell. The PUCCH issemi-statically configured between non-SUL and SUL in PCell if SUL isconfigured. The PUSCH can be dynamically switched between non-SUL andSUL if configured. No simultaneous PUSCH transmission on both is allowedat the same time. SRS can be simultaneously transmitted on both ULcarriers. The PDCCH order can indicate which UL to use for RACHtransmission. The RACH procedure (contention) can select non-SUL or SULPRACH resource depending on RSRP.

The SUL carrier can be configured as a complement to the normal UL (NUL)carrier. Switching between the normal carrier and the SUL carrier meansthat the UL transmissions move from the PUSCH on one carrier to theother carrier. This is done via an indication in DCI. If the MAC entityreceives a UL grant indicating a SUL switch while a Random Accessprocedure is ongoing, the MAC entity shall ignore the UL grant.

The Serving Cell configured with supplementaryUplink belongs to a singleTAG.

With Bandwidth Adaptation (BA), the receive and transmit bandwidth of aUE need not be as large as the bandwidth of the cell and can beadjusted: the width can be ordered to change (e.g. to shrink duringperiod of low activity to save power); the location can move in thefrequency domain (e.g. to increase scheduling flexibility); and thesubcarrier spacing can be ordered to change (e.g. to allow differentservices). A subset of the total cell bandwidth of a cell is referred toas a Bandwidth Part (BWP) and BA is achieved by configuring the UE withBWP(s) and telling the UE which of the configured BWPs is currently theactive one.

FIG. 8 shows a scenario where 3 different BWPs are configured.

As shown in FIG. 8, BWP1 may be configured with a width of 40 MHz andsubcarrier spacing of 15 kHz. BWP2 may be configured with a width of 10MHz and subcarrier spacing of 15 kHz. BWP3 may be configured with awidth of 20 MHz and subcarrier spacing of 60 kHz.

A Serving Cell may be configured with one or multiple BWPs. The BWPswitching for a Serving Cell is used to activate an inactive BWP anddeactivate an active BWP at a time. The BWP switching is controlled bythe PDCCH indicating a downlink assignment or an uplink grant, by thebandwidthPartInactivityTimer, or by the MAC entity itself uponinitiation of Random Access procedure. Upon addition of SpCell oractivation of a SCell, one BWP is initially active without receivingPDCCH indicating a downlink assignment or an uplink grant. The activeBWP for a Serving Cell is indicated by either RRC or PDCCH. For unpairedspectrum, a DL BWP is paired with a UL BWP, and BWP switching is commonfor both UL and DL.

On the active BWP for each activated Serving Cell configured with a BWP,the MAC entity shall apply normal operations including:

1> transmit on UL-SCH;

1> transmit on RACH;

1> monitor the PDCCH;

1> transmit PUCCH;

1> transmit SRS;

1> receive DL-SCH;

1> (re-)initialize any suspended configured uplink grants of configuredgrant Type 1 according to the stored configuration, if any, and to startin the symbol.

On the inactive BWP for each activated Serving Cell configured with aBWP, the MAC entity shall:

1> not transmit on UL-SCH;

1> not transmit on RACH;

1> not monitor the PDCCH;

1> not transmit PUCCH;

1> not transmit SRS;

1> not receive DL-SCH;

1> clear any configured downlink assignment and configured uplink grantof configured grant Type 2;

1> suspend any configured uplink grant of configured Type 1.

Upon initiation of the Random Access procedure, the MAC entity shall:

1> if PRACH occasions are configured for the active UL BWP:

2> perform the Random Access procedure on the active DL BWP and UL BWP.

1> else (i.e. PRACH occasions are not configured for the active UL BWP):

2> switch to initial DL BWP and UL BWP;

2> perform the Random Access procedure on the initial DL BWP and UL BWP.

If the MAC entity receives a PDCCH for BWP switching of a serving cell,the MAC entity shall:

1> if there is no ongoing Random Access procedure associated with this

Serving Cell; or

1> if the ongoing Random Access procedure associated with this ServingCell is successfully completed upon reception of this PDCCH addressed toC-RNTI:

2> perform BWP switching to a BWP indicated by the PDCCH.

If the MAC entity receives a PDCCH for BWP switching while a RandomAccess procedure is ongoing in the MAC entity, it is up to UEimplementation whether to switch BWP or ignore the PDCCH for BWPswitching, except for the PDCCH reception for BWP switching addressed tothe C-RNTI for successful Random Access procedure completion in whichcase the UE shall perform BWP switching to a BWP indicated by the PDCCH.Upon reception of the PDCCH for BWP switching other than successfulcontention resolution, if the MAC entity decides to perform BWPswitching, the MAC entity shall stop the ongoing Random Access procedureand initiate a Random Access procedure on the new activated BWP; if theMAC decides to ignore the PDCCH for BWP switching, the MAC entity shallcontinue with the ongoing Random Access procedure on the active BWP.

If the bwp-InactivityTimer is configured, the MAC entity shall for eachactivated

Serving Cell:

1> if the default-DL-BWP is configured, and the active DL BWP is not the

BWP indicated by the default-DL-BWP; or

1> if the default-DL-BWP is not configured, and the active DL BWP is notthe initial BWP:

2> if a PDCCH addressed to C-RNTI or CS-RNTI indicating downlinkassignment or uplink grant is received on the active BWP; or

2> if a MAC PDU is transmitted in a configured uplink grant or receivedin a configured downlink assignment:

3> if there is no ongoing random access procedure associated with thisServing Cell; or

3> if the ongoing Random Access procedure associated with this ServingCell is successfully completed upon reception of this PDCCH addressed toC-RNTI:

4> start or restart the bandwidthPartInactivityTimer associated with theactive DL BWP.

2> if a PDCCH for BWP switching is received on the active DL BWP, andthe MAC entity switches the active BWP:

3> start or restart the bwp-InactivityTimer associated with the activeDL BWP.

2> if Random Access procedure is initiated on this Serving Cell:

3> stop the bwp-InactivityTimer associated with the active DL BWP ofthis Serving Cell.

3> if the Serving Cell is SCell (other than PSCell):

4> stop the bwp-InactivityTimer associated with the active DL BWP ofSpCell, if running.

2> if the bwp-InactivityTimer associated with the active DL BWP expires:

3> if the default-DL-BWP is configured:

4> perform BWP switching to a BWP indicated by the default-DL-BWP.

3> else:

4> perform BWP switching to the initial DL BWP.

NR standalone operation on unlicensed band will be introduced. Whencongestion occurs on a particular BWP in unlicensed band, UE cannot moveto non-congested BWP by itself without indication on PDCCH or expiry ofBWP Inactivity Timer. Further, gNB may not quickly know whethercongestion occurs in the BWP. Thus, UE may not serve user service on theBWP in congestion.

FIG. 9 shows a method for selecting BWP according to an embodiment ofthe present invention.

In step S902, the UE may configure multiple bandwidth parts (BWPs) for acell. The multiple BWPs may be configured on unlicensed band.

In step S904, the UE may activate a first BWP among the multiple BWPs.

In step S906, the UE may acquire information on congestion of at leastone of the multiple BWPs. The information on congestion of the at leastone of the multiple BWPs may include information on congestion of thefirst BWP. The information on congestion of the at least one of themultiple BWPs may include information on congestion of the second BWP.The information on congestion may be acquired by carrier sensing. Theinformation on congestion may inform whether the at least one of themultiple BWPs is busy or free.

In step S908, the UE may switch to a second BWP among the multiple BWPsfrom the first BWPs, based on the acquired information on congestion.The UE may switch to the second BWP, when congestion level of the firstBWP is above a threshold informed by the cell. The UE may switch to thesecond BWP, when congestion level of the second BWP is below a thresholdinformed by the cell. The switching to the second BWP may includeconsidering the second BWP as an initial BWP or a default BWP.

Further, the UE may perform UL transmission on the second BWP via randomaccess procedure. The UE may communicate with at least one of a mobileterminal, a network or autonomous vehicles other than the UE.

According to embodiments of the present invention, the UE may provideuser service on BWP efficiently by moving to non-congested BWP byitself.

According to an embodiment of the present invention, when UE isconfigured with multiple uplink Bandwidth Parts (BWPs), if at least oneBWP is active, and if the congestion level of the active BWP is above athreshold indicated by the network for a certain time period, the UE mayperform BWP switching to another BWP. The switched BWP may be consideredas either default BWP or an initial BWP. Then, the UE may perform uplinktransmission on the switched BWP via random access procedure or viaPUSCH.

When the congestion level of the active BWP is above a thresholdindicated by the network for a certain time period, the UE may stop aBWP Inactivity Timer associated with the active BWP and the UE mayperform BWP switching to another BWP.

When the congestion level of the active BWP is above a thresholdindicated by the network for a certain time period, the UE may performBWP switching to another BWP and the UE may trigger random access on theswitched BWP.

When a condition of the BWP switching to another BWP is met, the UE mayperform the BWP switching based on the congestion level of the BWP. Forexample, when a condition of the BWP switching to other BWP is met, thatis, when congestion level of other BWP is below a threshold indicated bythe network, the UE may perform the BWP switching to the other BW from acurrently activated BWP. Otherwise, UE may not perform the BWP switchingto the BWP.

FIG. 10 shows a method for selecting BWP according to an embodiment ofthe present invention.

In step S1002, the UE may receive configuration on at least two BWPsfrom a cell. The UE may be configured with the at least two BWPs for oneDL of a cell according to the configuration. The configuration may berelated to addition or activation of serving cell. The BWPs may beoverlapped, contiguous or non-contiguous in frequency. All or some ofthe BWPs may be in either unlicensed band or licensed band. Theconfiguration may include a threshold indicated by the network (i.e.Cong_thres). The UE may be in RRC_IDLE, RRC_INACTIVE or RRC_CONNECTED.The UE may activate at least one BWP among the configured BWPs e.g. bythe PDCCH indicating a downlink assignment or an uplink grant or by RRCsignaling, and the UE may start a timer associated with the active BWP.The timer may be BWP Inactivity Timer.

Alternatively, the UE may perform addition of SpCell or activation of aSCell. The UE may be configured with more than one BWP for one DL of thecell. The UE may perform step S1006 and S1008 to select a BWP which willbe initially active.

In step S1004, the UE may measure congestion level of at least one BWPwhich is active. The congestion level may include information on qualityof the at least one BWP. The congestion level may include information onwhether the at least one BWP is occupied by other medium or not. Forexample, the UE may measure the congestion level of the at least one BWPby carrier sensing, such as LBT operation. In specific, the congestionlevel may be determined based on result of consecutive LBT operation.That is, the congestion level may be determined based on how many timesthe LBT failure is detected in series.

Further, the UE may measure congestion level of an inactive BWP. Or, theUE may only measure congestion level of BWPs of which measured quality(e.g. RSRP or RSRQ or RSSI) is above another threshold. Alternatively,the UE may acquire information on congestion level of at least one BWPfrom a network.

In step S1006, the UE may perform BWP switching to another BWP or mayselect another BWP based on the congestion level of at least one BWP(and the qualities of BWPs). If default BWP is configured, the switchedBWP may be a default BWP. Otherwise, the switched BWP may be an initialBWP. In other words, the UE may consider the switched BWP as the defaultBWP or the initial BWP. The BWP may be a DL BWP and/or UL BWP.

The UE may stop the timer associated with the active BWP based on thecongestion level of at least one BWP (and the qualities of BWPs). The UEmay stop the timer associated with the active BWP before or afterperforming BWP switching to another BWP. Or, UE stops the timerassociated with the active BWP before or after selecting another BWP.

For example, if the congestion level of an active BWP is above athreshold indicated by the network (i.e. Cong_thres), the UE may performBWP switching from the active BWP to another BWP in licensed band orunlicensed band, or selects another BWP.

For example, if the congestion level of an active BWP is above athreshold indicated by the network (i.e. Cong_thres), and if the qualityof another BWP is above a threshold indicated by the network, the UE mayperform BWP switching from the active BWP to another BWP in licensedband or unlicensed band, or selects another BWP.

For example, if the congestion level of an active BWP is the higher thanthe congestion level of another BWP, the UE may perform BWP switchingfrom the active BWP to another BWP in licensed band or unlicensed band,or selects another BWP.

For example, if the congestion level of an active BWP is the higher thanthe congestion level of another BWP, and if the quality of another BWPis above a threshold indicated by the network, the UE may perform BWPswitching from the active BWP to another BWP in licensed band orunlicensed band, or selects another BWP.

For example, if the congestion level of other BWP is below a thresholdindicated by the network, the UE may perform BWP switching from theactive BWP to the other BWP in licensed band or unlicensed band, orselects another BWP.

For example, if the congestion level of other BWP is lowest amongcongestion levels of all BWPs, the UE may perform BWP switching from theactive BWP to the other BWP with the lowest congestion level in licensedband or unlicensed band, or selects the BWP with the lowest congestionlevel.

For example, if the congestion level of a BWP is lowest among congestionlevels of all BWPs, and if the quality of the BWP with the lowestcongestion level is above a threshold indicated by the network, the UEmay perform BWP switching from the active BWP to the BWP with the lowestcongestion level in licensed band or unlicensed band, or selects the BWPwith the lowest congestion level.

When UE supports multiple BWPs, if one of the above conditions describedabove is met, the UE may additionally select another BWP instead ofperforming BWP switching to another BWP. In other words, the examplesfor performing BWP switching may be adapted to the BWP selection.

In step S1008, the UE may perform uplink transmission on the switched orselected BWP via random access procedure or via PUSCH. For example, theUE may perform uplink transmission for transmission of a RRC message.For example, the UE may perform uplink transmission via PUSCH fortransmission of user data or MAC Control Element.

According to an embodiment of the present invention, the MAC entity ofthe UE may perform the following procedure:

Upon addition of SpCell or activation of an SCell, the MAC entity shall:

1> if the congestion level of a BWP is lowest among congestion levels ofall BWPs for this serving cell; and

1> if the quality of the BWP with the lowest congestion level is above athreshold indicated by the network:

2> selects the BWP with the lowest congestion level;

2> activate the selected BWP;

2> initiate a Random Access procedure on the selected BWP.

Upon initiation of the Random Access procedure, the MAC entity shall:

1> if PRACH occasions are configured for the active UL BWP:

2> perform the Random Access procedure on the active DL BWP and UL BWP.

1> else (i.e. PRACH occasions are not configured for the active UL BWP):

2> switch to initial DL BWP and UL BWP;

2> perform the Random Access procedure on the initial DL BWP and UL BWP.

If the MAC entity receives a PDCCH for BWP switching of a serving cell,the MAC entity shall:

1> if there is no ongoing Random Access procedure associated with thisServing Cell; or

1> if the ongoing Random Access procedure associated with this ServingCell is successfully completed upon reception of this PDCCH addressed toC-RNTI (as specified in subclauses 5.1.4 and 5.1.5):

2> if congestion level of the BWP indicated by the PDCCH is lower than athreshold indicated by the gNB:

3> perform BWP switching to a BWP indicated by the PDCCH.

If the MAC entity receives a PDCCH for BWP switching while a RandomAccess procedure is ongoing in the MAC entity, it is up to UEimplementation whether to switch BWP or ignore the PDCCH for BWPswitching, except for the PDCCH reception for BWP switching addressed tothe C-RNTI for successful Random Access procedure completion (asspecified in subclauses 5.1.4 and 5.1.5) in which case the UE shallperform BWP switching to a BWP indicated by the PDCCH. Upon reception ofthe PDCCH for BWP switching other than successful contention resolution,if the MAC entity decides to perform BWP switching, the MAC entity shallstop the ongoing Random Access procedure and initiate a Random Accessprocedure on the new activated BWP; if the MAC decides to ignore thePDCCH for BWP switching, the MAC entity shall continue with the ongoingRandom Access procedure on the active BWP.

If the bwp-InactivityTimer is configured, the MAC entity shall for eachactivated Serving Cell:

1> if the default-DL-BWP is configured, and the active DL BWP is not theBWP indicated by the default-DL-BWP; or

1> if the default-DL-BWP is not configured, and the active DL BWP is notthe initial BWP:

2> if a PDCCH addressed to C-RNTI or CS-RNTI indicating downlinkassignment or uplink grant is received on the active BWP; or

2> if a MAC PDU is transmitted in a configured uplink grant or receivedin a configured downlink assignment:

3> if there is no ongoing random access procedure associated with thisServing Cell; or

3> if the ongoing Random Access procedure associated with this ServingCell is successfully completed upon reception of this PDCCH addressed toC-RNTI (as specified in subclauses 5.1.4 and 5.1.5):

4> start or restart the bandwidthPartInactivityTimer associated with theactive DL BWP.

2> if a PDCCH for BWP switching is received on the active DL BWP, andthe MAC entity switches the active BWP:

3> start or restart the bwp-InactivityTimer associated with the activeDL BWP.

2> if Random Access procedure is initiated on this Serving Cell:

3> stop the bwp-InactivityTimer associated with the active DL BWP ofthis Serving Cell.

3> if the Serving Cell is SCell (other than PSCell):

4> stop the bwp-InactivityTimer associated with the active DL BWP ofSpCell, if running.

2> if congestion level of the active DL BWP is higher than a thresholdindicated by gNB;

3> stop the bwp-InactivityTimer associated with the active DL BWP ofthis Serving Cell;

3> if the default-DL-BWP is configured:

4> perform BWP switching to a BWP indicated by the default-DL-BWP.

3> else:

4> perform BWP switching to the initial DL BWP.

3> initiate a Random Access procedure on a new activated BWP;

3> if the Serving Cell is SCell (other than PSCell):

4> stop the bwp-InactivityTimer associated with the active DL BWP ofSpCell, if running.

2> if congestion level of the active DL BWP is higher than congestionlevel of a DL BWP (which is inactive); and

2> if congestion level of the (inactive) DL BWP is lowest amongcongestion levels of all BWPs for this serving cell, or if congestionlevel of the (inactive) DL BWP is lower than a threshold indicated bygNB;

3> stop the bwp-InactivityTimer associated with the active DL BWP ofthis Serving Cell;

3> perform BWP switching to the (inactive) DL BWP;

3> initiate a Random Access procedure on a new activated BWP;

3> if the Serving Cell is SCell (other than PSCell):

4> stop the bwp-InactivityTimer associated with the active DL BWP ofSpCell, if running.

2> if the bwp-InactivityTimer associated with the active DL BWP expires:

3> if the default-DL-BWP is configured:

4> perform BWP switching to a BWP indicated by the default-DL-BWP.

3> else:

4> perform BWP switching to the initial DL BWP.

According to embodiments of the present invention, the UE may provideuser service on BWP efficiently by moving to non-congested BWP byitself.

FIG. 11 shows more detailed UE to implement an embodiment of the presentinvention. The present invention described above for UE side may beapplied to this embodiment.

A UE includes a processor 1110, a power management module 1111, abattery 1112, a display 1113, a keypad 1114, a subscriber identificationmodule (SIM) card 1115, a memory 1120, a transceiver 1130, one or moreantennas 1131, a speaker 1140, and a microphone 1141.

The processor 1110 may be configured to implement proposed functions,procedures and/or methods described in this description. Layers of theradio interface protocol may be implemented in the processor 1110. Theprocessor 1110 may include ASIC, other chipset, logic circuit and/ordata processing device. The processor 1110 may be an applicationprocessor (AP). The processor 1110 may include at least one of a digitalsignal processor (DSP), a central processing unit (CPU), a graphicsprocessing unit (GPU), a modem (modulator and demodulator). An exampleof the processor 1110 may be found in SNAPDRAGON™ series of processorsmade by Qualcomm®, EXYNOS™ series of processors made by Samsung®, Aseries of processors made by Apple®, HELIO™ series of processors made byMediaTek®, ATOM™ series of processors made by Intel® or a correspondingnext generation processor.

According to an embodiment of the present invention, the processor 1110may be configured to configure multiple bandwidth parts (BWPs) for acell. The multiple BWPs may be configured on unlicensed band.

The processor 1110 may be configured to activate a first BWP among themultiple BWPs.

The processor 1110 may be configured to acquire information oncongestion of at least one of the multiple BWPs. The information oncongestion of the at least one of the multiple BWPs may includeinformation on congestion of the first BWP. The information oncongestion of the at least one of the multiple BWPs may includeinformation on congestion of the second BWP. The information oncongestion may be acquired by carrier sensing. The information oncongestion may inform whether the at least one of the multiple BWPs isbusy or free.

The processor 1110 may be configured to switch to a second BWP among themultiple BWPs from the first BWPs, based on the acquired information oncongestion. The UE may switch to the second BWP, when congestion levelof the first BWP is above a threshold informed by the cell. The UE mayswitch to the second BWP, when congestion level of the second BWP isbelow a threshold informed by the cell. The switching to the second BWPmay include considering the second BWP as an initial BWP or a defaultBWP.

Further, the processor 1110 may be configured to perform UL transmissionon the second BWP via random access procedure. The processor 1110 may beconfigured to communicate with at least one of a mobile terminal, anetwork or autonomous vehicles other than the UE.

The power management module 1111 manages power for the processor 1110and/or the transceiver 1130. The battery 1112 supplies power to thepower management module 1111. The display 1113 outputs results processedby the processor 1110. The keypad 1114 receives inputs to be used by theprocessor 1110. The keypad 1114 may be shown on the display 1113. TheSIM card 1115 is an integrated circuit that is intended to securelystore the international mobile subscriber identity (IMSI) number and itsrelated key, which are used to identify and authenticate subscribers onmobile telephony devices (such as mobile phones and computers). It isalso possible to store contact information on many SIM cards.

The memory 1120 is operatively coupled with the processor 1110 andstores a variety of information to operate the processor 1110. Thememory 1120 may include ROM, RAM, flash memory, memory card, storagemedium and/or other storage device. When the embodiments are implementedin software, the techniques described herein can be implemented withmodules (e.g., procedures, functions, and so on) that perform thefunctions described herein. The modules can be stored in the memory 1120and executed by the processor 1110. The memory 1120 can be implementedwithin the processor 1110 or external to the processor 1110 in whichcase those can be communicatively coupled to the processor 1110 viavarious means as is known in the art.

The transceiver 1130 is operatively coupled with the processor 1110, andtransmits and/or receives a radio signal. The transceiver 1130 includesa transmitter and a receiver. The transceiver 1130 may include basebandcircuitry to process radio frequency signals. The transceiver 1130controls the one or more antennas 1131 to transmit and/or receive aradio signal.

The speaker 1140 outputs sound-related results processed by theprocessor 1110. The microphone 1141 receives sound-related inputs to beused by the processor 1110.

According to embodiments of the present invention, the UE may provideuser service on BWP efficiently by moving to non-congested BWP byitself.

The present invention may be applied to various future technologies,such as AI, robots, autonomous-driving/self-driving vehicles, and/orextended reality (XR).

AI refers to artificial intelligence and/or the field of studyingmethodology for making it. Machine learning is a field of studyingmethodologies that define and solve various problems dealt with in AI.Machine learning may be defined as an algorithm that enhances theperformance of a task through a steady experience with any task.

An artificial neural network (ANN) is a model used in machine learning.It can mean a whole model of problem-solving ability, consisting ofartificial neurons (nodes) that form a network of synapses. An ANN canbe defined by a connection pattern between neurons in different layers,a learning process for updating model parameters, and/or an activationfunction for generating an output value. An ANN may include an inputlayer, an output layer, and optionally one or more hidden layers. Eachlayer may contain one or more neurons, and an ANN may include a synapsethat links neurons to neurons. In an ANN, each neuron can output asummation of the activation function for input signals, weights, anddeflections input through the synapse. Model parameters are parametersdetermined through learning, including deflection of neurons and/orweights of synaptic connections. The hyper-parameter means a parameterto be set in the machine learning algorithm before learning, andincludes a learning rate, a repetition number, a mini batch size, aninitialization function, etc. The objective of the ANN learning can beseen as determining the model parameters that minimize the lossfunction. The loss function can be used as an index to determine optimalmodel parameters in learning process of ANN.

Machine learning can be divided into supervised learning, unsupervisedlearning, and reinforcement learning, depending on the learning method.Supervised learning is a method of learning ANN with labels given tolearning data. Labels are the answers (or result values) that ANN mustinfer when learning data is input to ANN. Unsupervised learning can meana method of learning ANN without labels given to learning data.Reinforcement learning can mean a learning method in which an agentdefined in an environment learns to select a behavior and/or sequence ofactions that maximizes cumulative compensation in each state.

Machine learning, which is implemented as a deep neural network (DNN)that includes multiple hidden layers among ANN, is also called deeplearning. Deep learning is part of machine learning. In the following,machine learning is used to mean deep learning.

A robot can mean a machine that automatically processes or operates agiven task by its own abilities. In particular, a robot having afunction of recognizing the environment and performingself-determination and operation can be referred to as an intelligentrobot. Robots can be classified into industrial, medical, household,military, etc., depending on the purpose and field of use. The robot mayinclude a driving unit including an actuator and/or a motor to performvarious physical operations such as moving a robot joint. In addition,the movable robot may include a wheel, a break, a propeller, etc., in adriving unit, and can travel on the ground or fly in the air through thedriving unit.

The autonomous-driving refers to a technique of self-driving, and anautonomous vehicle refers to a vehicle that travels without a user'soperation or with a minimum operation of a user. For example,autonomous-driving may include techniques for maintaining a lane whiledriving, techniques for automatically controlling speed such as adaptivecruise control, techniques for automatically traveling along apredetermined route, and techniques for traveling by setting a routeautomatically when a destination is set. The autonomous vehicle mayinclude a vehicle having only an internal combustion engine, a hybridvehicle having an internal combustion engine and an electric motortogether, and an electric vehicle having only an electric motor, and mayinclude not only an automobile but also a train, a motorcycle, etc. Theautonomous vehicle can be regarded as a robot having an autonomousdriving function.

XR are collectively referred to as VR, AR, and MR. VR technologyprovides real-world objects and/or backgrounds only as computer graphic(CG) images, AR technology provides CG images that is virtually createdon real object images, and MR technology is a computer graphicstechnology that mixes and combines virtual objects in the real world. MRtechnology is similar to AR technology in that it shows real and virtualobjects together. However, in the AR technology, the virtual object isused as a complement to the real object, whereas in the MR technology,the virtual object and the real object are used in an equal manner. XRtechnology can be applied to HMD, head-up display (HUD), mobile phone,tablet PC, laptop, desktop, TV, digital signage. A device to which theXR technology is applied may be referred to as an XR device.

FIG. 12 shows an example of an AI device to which the technical featuresof the present invention can be applied.

The AI device 1200 may be implemented as a stationary device or a mobiledevice, such as a TV, a projector, a mobile phone, a smartphone, adesktop computer, a notebook, a digital broadcasting terminal, a PDA, aPMP, a navigation device, a tablet PC, a wearable device, a set-top box(STB), a digital multimedia broadcasting (DMB) receiver, a radio, awashing machine, a refrigerator, a digital signage, a robot, a vehicle,etc.

Referring to FIG. 12, the AI device 1200 may include a communicationpart 1210, an input part 1220, a learning processor 1230, a sensing part1240, an output part 1250, a memory 1260, and a processor 1270.

The communication part 1210 can transmit and/or receive data to and/orfrom external devices such as the AI devices and the AI server usingwire and/or wireless communication technology. For example, thecommunication part 1210 can transmit and/or receive sensor information,a user input, a learning model, and a control signal with externaldevices. The communication technology used by the communication part1210 may include a global system for mobile communication (GSM), a codedivision multiple access (CDMA), an LTE/LTE-A, a 5G, a WLAN, a Wi-Fi,Bluetooth™, radio frequency identification (RFID), infrared dataassociation (IrDA), ZigBee, and/or near field communication (NFC).

The input part 1220 can acquire various kinds of data. The input part1220 may include a camera for inputting a video signal, a microphone forreceiving an audio signal, and a user input part for receivinginformation from a user. A camera and/or a microphone may be treated asa sensor, and a signal obtained from a camera and/or a microphone may bereferred to as sensing data and/or sensor information. The input part1220 can acquire input data to be used when acquiring an output usinglearning data and a learning model for model learning. The input part1220 may obtain raw input data, in which case the processor 1270 or thelearning processor 1230 may extract input features by preprocessing theinput data.

The learning processor 1230 may learn a model composed of an ANN usinglearning data. The learned ANN can be referred to as a learning model.The learning model can be used to infer result values for new input datarather than learning data, and the inferred values can be used as abasis for determining which actions to perform. The learning processor1230 may perform AI processing together with the learning processor ofthe AI server. The learning processor 1230 may include a memoryintegrated and/or implemented in the AI device 1200. Alternatively, thelearning processor 1230 may be implemented using the memory 1260, anexternal memory directly coupled to the AI device 1200, and/or a memorymaintained in an external device.

The sensing part 1240 may acquire at least one of internal informationof the AI device 1200, environment information of the AI device 1200,and/or the user information using various sensors. The sensors includedin the sensing part 1240 may include a proximity sensor, an illuminancesensor, an acceleration sensor, a magnetic sensor, a gyro sensor, aninertial sensor, an RGB sensor, an IR sensor, a fingerprint recognitionsensor, an ultrasonic sensor, an optical sensor, a microphone, a lightdetection and ranging (LIDAR), and/or a radar.

The output part 1250 may generate an output related to visual, auditory,tactile, etc. The output part 1250 may include a display unit foroutputting visual information, a speaker for outputting auditoryinformation, and/or a haptic module for outputting tactile information.

The memory 1260 may store data that supports various functions of the AIdevice 1200. For example, the memory 1260 may store input data acquiredby the input part 1220, learning data, a learning model, a learninghistory, etc.

The processor 1270 may determine at least one executable operation ofthe AI device 1200 based on information determined and/or generatedusing a data analysis algorithm and/or a machine learning algorithm. Theprocessor 1270 may then control the components of the AI device 1200 toperform the determined operation. The processor 1270 may request,retrieve, receive, and/or utilize data in the learning processor 1230and/or the memory 1260, and may control the components of the AI device1200 to execute the predicted operation and/or the operation determinedto be desirable among the at least one executable operation. Theprocessor 1270 may generate a control signal for controlling theexternal device, and may transmit the generated control signal to theexternal device, when the external device needs to be linked to performthe determined operation. The processor 1270 may obtain the intentioninformation for the user input and determine the user's requirementsbased on the obtained intention information. The processor 1270 may useat least one of a speech-to-text (STT) engine for converting speechinput into a text string and/or a natural language processing (NLP)engine for acquiring intention information of a natural language, toobtain the intention information corresponding to the user input. Atleast one of the STT engine and/or the NLP engine may be configured asan ANN, at least a part of which is learned according to a machinelearning algorithm. At least one of the STT engine and/or the NLP enginemay be learned by the learning processor 1230 and/or learned by thelearning processor of the AI server, and/or learned by their distributedprocessing. The processor 1270 may collect history information includingthe operation contents of the AI device 1200 and/or the user's feedbackon the operation, etc. The processor 1270 may store the collectedhistory information in the memory 1260 and/or the learning processor1230, and/or transmit to an external device such as the AI server. Thecollected history information can be used to update the learning model.The processor 1270 may control at least some of the components of AIdevice 1200 to drive an application program stored in memory 1260.Furthermore, the processor 1270 may operate two or more of thecomponents included in the AI device 1200 in combination with each otherfor driving the application program.

FIG. 13 shows an example of an AI system to which the technical featuresof the present invention can be applied.

Referring to FIG. 13, in the AI system, at least one of an AI server1320, a robot 1310 a, an autonomous vehicle 1310 b, an XR device 1310 c,a smartphone 1310 d and/or a home appliance 1310 e is connected to acloud network 1300. The robot 1310 a, the autonomous vehicle 1310 b, theXR device 1310 c, the smartphone 1310 d, and/or the home appliance 1310e to which the AI technology is applied may be referred to as AI devices1310 a to 1310 e.

The cloud network 1300 may refer to a network that forms part of a cloudcomputing infrastructure and/or resides in a cloud computinginfrastructure. The cloud network 1300 may be configured using a 3Gnetwork, a 4G or LTE network, and/or a 5G network. That is, each of thedevices 1310 a to 1310 e and 1320 consisting the AI system may beconnected to each other through the cloud network 1300. In particular,each of the devices 1310 a to 1310 e and 1320 may communicate with eachother through a base station, but may directly communicate with eachother without using a base station.

The AI server 1300 may include a server for performing AI processing anda server for performing operations on big data. The AI server 1300 isconnected to at least one or more of AI devices constituting the AIsystem, i.e. the robot 1310 a, the autonomous vehicle 1310 b, the XRdevice 1310 c, the smartphone 1310 d and/or the home appliance 1310 ethrough the cloud network 1300, and may assist at least some AIprocessing of the connected AI devices 1310 a to 1310 e. The AI server1300 can learn the ANN according to the machine learning algorithm onbehalf of the AI devices 1310 a to 1310 e, and can directly store thelearning models and/or transmit them to the AI devices 1310 a to 1310 e.The AI server 1300 may receive the input data from the AI devices 1310 ato 1310 e, infer the result value with respect to the received inputdata using the learning model, generate a response and/or a controlcommand based on the inferred result value, and transmit the generateddata to the AI devices 1310 a to 1310 e. Alternatively, the AI devices1310 a to 1310 e may directly infer a result value for the input datausing a learning model, and generate a response and/or a control commandbased on the inferred result value.

Various embodiments of the AI devices 1310 a to 1310 e to which thetechnical features of the present invention can be applied will bedescribed. The AI devices 1310 a to 1310 e shown in FIG. 13 can be seenas specific embodiments of the AI device 1200 shown in FIG. 12.

In this document, the term “/” and “,” should be interpreted to indicate“and/or.” For instance, the expression “A/B” may mean “A and/or B.”Further, “A, B” may mean “A and/or B.” Further, “A/B/C” may mean “atleast one of A, B, and/or C.” Also, “A, B, C” may mean “at least one ofA, B, and/or C.”

Further, in the document, the term “or” should be interpreted toindicate “and/or.” For instance, the expression “A or B” may comprise 1)only A, 2) only B, and/or 3) both A and B. In other words, the term “or”in this document should be interpreted to indicate “additionally oralternatively.”

In view of the exemplary systems described herein, methodologies thatmay be implemented in accordance with the disclosed subject matter havebeen described with reference to several flow diagrams. While forpurposed of simplicity, the methodologies are shown and described as aseries of steps or blocks, it is to be understood and appreciated thatthe claimed subject matter is not limited by the order of the steps orblocks, as some steps may occur in different orders or concurrently withother steps from what is depicted and described herein. Moreover, oneskilled in the art would understand that the steps illustrated in theflow diagram are not exclusive and other steps may be included or one ormore of the steps in the example flow diagram may be deleted withoutaffecting the scope of the present disclosure.

What has been described above includes examples of the various aspects.It is, of course, not possible to describe every conceivable combinationof components or methodologies for purposes of describing the variousaspects, but one of ordinary skill in the art may recognize that manyfurther combinations and permutations are possible. Accordingly, thesubject specification is intended to embrace all such alternations,modifications and variations that fall within the scope of the appendedclaims.

1. A method performed by a wireless device configured to operate in awireless communication system, the method comprising: configuringmultiple bandwidth parts (BWPs) for a cell; activating a first BWP amongthe multiple BWPs to be an active BWP; acquiring information oncongestion of the first BWP to determine whether the first BWP iscongested or not; switching the active BWP from the first BWP to asecond BWP among the multiple BWPs based on being determined that thefirst BWP is congested; performing a random access procedure on thesecond BWP; and performing uplink transmission of a media access control(MAC) control element (CE) on the second BWP.
 2. The method of claim 1,wherein the multiple BWPs are configured on an unlicensed band. 3.(canceled)
 4. The method of claim 1, wherein information on congestionof the second BWP is further acquired.
 5. The method of claim 1, whereinit is determined that the first BWP is congested based on a congestionlevel of the first BWP being above a threshold informed by the cell. 6.(canceled)
 7. The method of claim 1, wherein the information oncongestion of the first BWP is acquired by carrier sensing. 8.(canceled)
 9. The method of claim 1, wherein the second BWP is aninitial BWP or a default BWP.
 10. (canceled)
 11. The method of claim 1,wherein the wireless device communicates with at least one of a mobileterminal, a network or autonomous vehicles other than the wirelessdevice.
 12. A wireless device configured to operate in a wirelesscommunication system, the UE comprising: a memory; a transceiver; and aprocessor, operably coupled to the memory and the transceiver, whereinthe wireless device is configured to: configure multiple bandwidth parts(BWPs) for a cell; activate a first BWP among the multiple BWPs to be anactive BWP; acquire information on congestion of the first BWP todetermine whether the first BWP is congested or not; switch the activeBWP from the first BWP to a second BWP among the multiple BWPs based onbeing determined that the first BWP is congested; performing a randomaccess procedure on the second BWP; and performing uplink transmissionof a media access control (MAC) control element (CE) on the second BWP.13. The UE of claim 12, wherein the multiple BWPs are configured on anunlicensed band.
 14. (canceled)
 15. A processor for a wirelesscommunication device in a wireless communication system, wherein theprocessor is configured to control the wireless communication device to:configure multiple bandwidth parts (BWPs) for a cell; activate a firstBWP among the multiple BWPs to be an active BWP; acquire information oncongestion of the first BWP to determine whether the first BWP iscongested or not; switch the active BWP from the first BWP to a secondBWP among the multiple BWPs based on being determined that the first BWPis congested; performing a random access procedure on the second BWP;and performing uplink transmission of a media access control (MAC)control element (CE) on the second BWP.